Every single electronic device consumes electrical energy to operate. The electrical energy can be supplied from a socket via a power cord of which one end is connected to the electronic device and the other end is connected to the socket by means of a plug or from a battery that generates the electronical energy through chemical reaction. Such electronic devices are designed in various forms for use in diverse fields. For example, all types of household electrical appliances operate on electricity. Also, almost all of the devices for use in factories and offices operate on electricity.
As aforementioned, the electricity is the most common and essential source of energy in our everyday lives. Recently, most countries are striving to generate electricity as one of the best alternative energies safely at low costs and conducting researches on how to save electrical energy.
Meanwhile, the household appliances are becoming smarter in line with the development of the information and communication technology. The household appliances are evolving to intelligent electronic devices equipped with supplementary functions including the communication function in addition to their unique functions. Such advanced household appliances are called smart household appliances. Typically, smart household appliances are likely to be equipped with a self-power measurement function and capable of sharing measurement results though a wired/wireless communication interface. The smart household appliances allow users to control them remotely and use them for various purposes, e.g., for measuring and reporting power consumptions thereof.
However, it is predicted that it takes relatively long time for smart household appliances to be popularized in the market. Furthermore, the high switching costs from the legacy household appliances to the smart household appliances slow down the popularization of the smart household appliances.
Smart-plug is a transition technology developed for making it possible to implement a smart home system with the legacy household appliances and, typically, the smart plug has a function of measuring power consumption of a household appliance and transmitting the measurement result to another device. The smart plug makes it possible to implement the smart home with the legacy household appliances. That is, the smart plug is capable of measuring the power consumptions of the electronic devices connected thereto in both the idle and active states and reporting the state-specific power consumptions to the user. It may also be possible for the user to control the smart plug remotely to turn on/off the electronic device connected thereto.